[PATCH] DVB: Fix locking problems and code cleanup (ded92846) · Commits · e / devices / android_kernel_sony_msm8994

drivers/media/dvb/dvb-core/dvb_ca_en50221.c

+23 −46

Original line number	Original line	Diff line number	Diff line
	@@ -35,7 +35,7 @@
	#include <linux/moduleparam.h>		#include <linux/moduleparam.h>
	#include <linux/vmalloc.h>		#include <linux/vmalloc.h>
	#include <linux/delay.h>		#include <linux/delay.h>
	#include <linux/rwsem.h>		#include <linux/spinlock.h>
	#include <linux/sched.h>		#include <linux/sched.h>

	#include "dvb_ca_en50221.h"		#include "dvb_ca_en50221.h"
	@@ -111,9 +111,6 @@ struct dvb_ca_slot {
	/* size of the buffer to use when talking to the CAM */		/* size of the buffer to use when talking to the CAM */
	int link_buf_size;		int link_buf_size;

	/* semaphore for syncing access to slot structure */
	struct rw_semaphore sem;

	/* buffer for incoming packets */		/* buffer for incoming packets */
	struct dvb_ringbuffer rx_buffer;		struct dvb_ringbuffer rx_buffer;

	@@ -602,14 +599,11 @@ static int dvb_ca_en50221_read_data(struct dvb_ca_private ca, int slot, u8 eb
	if (ebuf == NULL) {		if (ebuf == NULL) {
	int buf_free;		int buf_free;

	down_read(&ca->slot_info[slot].sem);
	if (ca->slot_info[slot].rx_buffer.data == NULL) {		if (ca->slot_info[slot].rx_buffer.data == NULL) {
	up_read(&ca->slot_info[slot].sem);
	status = -EIO;		status = -EIO;
	goto exit;		goto exit;
	}		}
	buf_free = dvb_ringbuffer_free(&ca->slot_info[slot].rx_buffer);		buf_free = dvb_ringbuffer_free(&ca->slot_info[slot].rx_buffer);
	up_read(&ca->slot_info[slot].sem);

	if (buf_free < (ca->slot_info[slot].link_buf_size + DVB_RINGBUFFER_PKTHDRSIZE)) {		if (buf_free < (ca->slot_info[slot].link_buf_size + DVB_RINGBUFFER_PKTHDRSIZE)) {
	status = -EAGAIN;		status = -EAGAIN;
	@@ -680,14 +674,11 @@ static int dvb_ca_en50221_read_data(struct dvb_ca_private ca, int slot, u8 eb

	/* OK, add it to the receive buffer, or copy into external buffer if supplied */		/* OK, add it to the receive buffer, or copy into external buffer if supplied */
	if (ebuf == NULL) {		if (ebuf == NULL) {
	down_read(&ca->slot_info[slot].sem);
	if (ca->slot_info[slot].rx_buffer.data == NULL) {		if (ca->slot_info[slot].rx_buffer.data == NULL) {
	up_read(&ca->slot_info[slot].sem);
	status = -EIO;		status = -EIO;
	goto exit;		goto exit;
	}		}
	dvb_ringbuffer_pkt_write(&ca->slot_info[slot].rx_buffer, buf, bytes_read);		dvb_ringbuffer_pkt_write(&ca->slot_info[slot].rx_buffer, buf, bytes_read);
	up_read(&ca->slot_info[slot].sem);
	} else {		} else {
	memcpy(ebuf, buf, bytes_read);		memcpy(ebuf, buf, bytes_read);
	}		}
	@@ -802,12 +793,8 @@ static int dvb_ca_en50221_slot_shutdown(struct dvb_ca_private *ca, int slot)
	{		{
	dprintk("%s\n", __FUNCTION__);		dprintk("%s\n", __FUNCTION__);

	down_write(&ca->slot_info[slot].sem);
	ca->pub->slot_shutdown(ca->pub, slot);		ca->pub->slot_shutdown(ca->pub, slot);
	ca->slot_info[slot].slot_state = DVB_CA_SLOTSTATE_NONE;		ca->slot_info[slot].slot_state = DVB_CA_SLOTSTATE_NONE;
	vfree(ca->slot_info[slot].rx_buffer.data);
	ca->slot_info[slot].rx_buffer.data = NULL;
	up_write(&ca->slot_info[slot].sem);

	/* need to wake up all processes to check if they're now		/* need to wake up all processes to check if they're now
	trying to write to a defunct CAM */		trying to write to a defunct CAM */
	@@ -893,7 +880,7 @@ void dvb_ca_en50221_frda_irq(struct dvb_ca_en50221 *pubca, int slot)

	case DVB_CA_SLOTSTATE_RUNNING:		case DVB_CA_SLOTSTATE_RUNNING:
	if (ca->open)		if (ca->open)
	dvb_ca_en50221_read_data(ca, slot, NULL, 0);		dvb_ca_en50221_thread_wakeup(ca);
	break;		break;
	}		}
	}		}
	@@ -1127,6 +1114,7 @@ static int dvb_ca_en50221_thread(void *data)
	break;		break;
	}		}

			if (ca->slot_info[slot].rx_buffer.data == NULL) {
	rxbuf = vmalloc(RX_BUFFER_SIZE);		rxbuf = vmalloc(RX_BUFFER_SIZE);
	if (rxbuf == NULL) {		if (rxbuf == NULL) {
	printk("dvb_ca adapter %d: Unable to allocate CAM rx buffer :(\n", ca->dvbdev->adapter->num);		printk("dvb_ca adapter %d: Unable to allocate CAM rx buffer :(\n", ca->dvbdev->adapter->num);
	@@ -1134,9 +1122,8 @@ static int dvb_ca_en50221_thread(void *data)
	dvb_ca_en50221_thread_update_delay(ca);		dvb_ca_en50221_thread_update_delay(ca);
	break;		break;
	}		}
	down_write(&ca->slot_info[slot].sem);
	dvb_ringbuffer_init(&ca->slot_info[slot].rx_buffer, rxbuf, RX_BUFFER_SIZE);		dvb_ringbuffer_init(&ca->slot_info[slot].rx_buffer, rxbuf, RX_BUFFER_SIZE);
	up_write(&ca->slot_info[slot].sem);		}

	ca->pub->slot_ts_enable(ca->pub, slot);		ca->pub->slot_ts_enable(ca->pub, slot);
	ca->slot_info[slot].slot_state = DVB_CA_SLOTSTATE_RUNNING;		ca->slot_info[slot].slot_state = DVB_CA_SLOTSTATE_RUNNING;
	@@ -1148,11 +1135,7 @@ static int dvb_ca_en50221_thread(void *data)
	if (!ca->open)		if (!ca->open)
	continue;		continue;

	// no need to poll if the CAM supports IRQs		// poll slots for data
	if (ca->slot_info[slot].da_irq_supported)
	break;

	// poll mode
	pktcount = 0;		pktcount = 0;
	while ((status = dvb_ca_en50221_read_data(ca, slot, NULL, 0)) > 0) {		while ((status = dvb_ca_en50221_read_data(ca, slot, NULL, 0)) > 0) {
	if (!ca->open)		if (!ca->open)
	@@ -1367,12 +1350,13 @@ exit:
	/**		/**
	* Condition for waking up in dvb_ca_en50221_io_read_condition		* Condition for waking up in dvb_ca_en50221_io_read_condition
	*/		*/
	static int dvb_ca_en50221_io_read_condition(struct dvb_ca_private ca, int result, int *_slot)		static int dvb_ca_en50221_io_read_condition(struct dvb_ca_private *ca,
			int result, int _slot)
	{		{
	int slot;		int slot;
	int slot_count = 0;		int slot_count = 0;
	int idx;		int idx;
	int fraglen;		size_t fraglen;
	int connection_id = -1;		int connection_id = -1;
	int found = 0;		int found = 0;
	u8 hdr[2];		u8 hdr[2];
	@@ -1382,10 +1366,7 @@ static int dvb_ca_en50221_io_read_condition(struct dvb_ca_private ca, int resu
	if (ca->slot_info[slot].slot_state != DVB_CA_SLOTSTATE_RUNNING)		if (ca->slot_info[slot].slot_state != DVB_CA_SLOTSTATE_RUNNING)
	goto nextslot;		goto nextslot;

	down_read(&ca->slot_info[slot].sem);

	if (ca->slot_info[slot].rx_buffer.data == NULL) {		if (ca->slot_info[slot].rx_buffer.data == NULL) {
	up_read(&ca->slot_info[slot].sem);
	return 0;		return 0;
	}		}

	@@ -1403,9 +1384,6 @@ static int dvb_ca_en50221_io_read_condition(struct dvb_ca_private ca, int resu
	idx = dvb_ringbuffer_pkt_next(&ca->slot_info[slot].rx_buffer, idx, &fraglen);		idx = dvb_ringbuffer_pkt_next(&ca->slot_info[slot].rx_buffer, idx, &fraglen);
	}		}

	if (!found)
	up_read(&ca->slot_info[slot].sem);

	nextslot:		nextslot:
	slot = (slot + 1) % ca->slot_count;		slot = (slot + 1) % ca->slot_count;
	slot_count++;		slot_count++;
	@@ -1512,7 +1490,6 @@ static ssize_t dvb_ca_en50221_io_read(struct file file, char __user buf,
	status = pktlen;		status = pktlen;

	exit:		exit:
	up_read(&ca->slot_info[slot].sem);
	return status;		return status;
	}		}

	@@ -1544,11 +1521,11 @@ static int dvb_ca_en50221_io_open(struct inode inode, struct file file)
	for (i = 0; i < ca->slot_count; i++) {		for (i = 0; i < ca->slot_count; i++) {

	if (ca->slot_info[i].slot_state == DVB_CA_SLOTSTATE_RUNNING) {		if (ca->slot_info[i].slot_state == DVB_CA_SLOTSTATE_RUNNING) {
	down_write(&ca->slot_info[i].sem);
	if (ca->slot_info[i].rx_buffer.data != NULL) {		if (ca->slot_info[i].rx_buffer.data != NULL) {
			/* it is safe to call this here without locks because
			* ca->open == 0. Data is not read in this case */
	dvb_ringbuffer_flush(&ca->slot_info[i].rx_buffer);		dvb_ringbuffer_flush(&ca->slot_info[i].rx_buffer);
	}		}
	up_write(&ca->slot_info[i].sem);
	}		}
	}		}

	@@ -1607,7 +1584,6 @@ static unsigned int dvb_ca_en50221_io_poll(struct file file, poll_table wait)
	dprintk("%s\n", __FUNCTION__);		dprintk("%s\n", __FUNCTION__);

	if (dvb_ca_en50221_io_read_condition(ca, &result, &slot) == 1) {		if (dvb_ca_en50221_io_read_condition(ca, &result, &slot) == 1) {
	up_read(&ca->slot_info[slot].sem);
	mask \|= POLLIN;		mask \|= POLLIN;
	}		}

	@@ -1619,7 +1595,6 @@ static unsigned int dvb_ca_en50221_io_poll(struct file file, poll_table wait)
	poll_wait(file, &ca->wait_queue, wait);		poll_wait(file, &ca->wait_queue, wait);

	if (dvb_ca_en50221_io_read_condition(ca, &result, &slot) == 1) {		if (dvb_ca_en50221_io_read_condition(ca, &result, &slot) == 1) {
	up_read(&ca->slot_info[slot].sem);
	mask \|= POLLIN;		mask \|= POLLIN;
	}		}

	@@ -1709,7 +1684,6 @@ int dvb_ca_en50221_init(struct dvb_adapter *dvb_adapter,
	ca->slot_info[i].slot_state = DVB_CA_SLOTSTATE_NONE;		ca->slot_info[i].slot_state = DVB_CA_SLOTSTATE_NONE;
	atomic_set(&ca->slot_info[i].camchange_count, 0);		atomic_set(&ca->slot_info[i].camchange_count, 0);
	ca->slot_info[i].camchange_type = DVB_CA_EN50221_CAMCHANGE_REMOVED;		ca->slot_info[i].camchange_type = DVB_CA_EN50221_CAMCHANGE_REMOVED;
	init_rwsem(&ca->slot_info[i].sem);
	}		}

	if (signal_pending(current)) {		if (signal_pending(current)) {
	@@ -1771,6 +1745,9 @@ void dvb_ca_en50221_release(struct dvb_ca_en50221 *pubca)

	for (i = 0; i < ca->slot_count; i++) {		for (i = 0; i < ca->slot_count; i++) {
	dvb_ca_en50221_slot_shutdown(ca, i);		dvb_ca_en50221_slot_shutdown(ca, i);
			if (ca->slot_info[i].rx_buffer.data != NULL) {
			vfree(ca->slot_info[i].rx_buffer.data);
			}
	}		}
	kfree(ca->slot_info);		kfree(ca->slot_info);
	dvb_unregister_device(ca->dvbdev);		dvb_unregister_device(ca->dvbdev);